Electronic/electric components such as light-sensitive sensors (CMOS chips), light emitting diodes (LED) etc. have been increasingly employed in medical devices, for example in endoscopic devices. Especially endoscopes/coloscopes have at the distal end of a flexible endoscope shaft a so called endoscope head in which a number of functional units such as, inter alia, an optical means comprising a lens system and a light-sensitive microchip, a illumination means, preferably a working channel as well as a flushing means, where appropriate, are accommodated. Because of the lack of space existing within the endoscope head the individual functional units are built very closely to each other so that they might have a mutual thermal influence. In other words, especially the illumination means develops thermal energy which must not be discharged exclusively via the outer surface of the endoscope head so as not to damage the adjacent biological tissue (colon, stomach, esophagus etc. of the patient). This thermal energy further results in impairments of the optical means, especially of the usually heat-sensitive light sensor. For this reason, functional units irradiating thermal energy and/or heat-sensitive functional units are in addition actively cooled by means of an integrated cooling device.
From U.S. Pat. No. 7,413,543 B2 a medical endoscope of the relevant species is known. The endoscope head of this known endoscope is formed by a sleeve-like endoscope cap closed at the end face by an integrally formed end plate in which a lens system, an electronic control including a light-sensitive sensor chip, an electric conductor plate having LED positioned thereon as well as a cooling device are incorporated as functional units. Moreover, a working channel which opens to the outside at the end plate is axially passed through the endoscope head.
The cooling device consists of a separate heat exchanger in the form of a semi-cylindrical cooling chamber collar having a fluid inlet and outlet inserted in the endoscope cap. The distal open end face of the separate cooling chamber collar is closed by the electric conductor plate so that cooling fluid directly flows toward the conductor plate inside the chamber and thus cools the LED mounted thereon on the rear side. Simultaneously, the separate cooling chamber collar serves as a support for the lens system. In the end plate through-bores are formed so that the LED can emit light to the outside through the bores after inserting the cooling chamber collar in the endoscope cap. At the proximal closed end face of the cooling chamber collar the electronic control including a light-sensitive sensor chip is arranged so that also the sensor is somewhat cooled by the cooling chamber collar. At the same time, the cooling chamber collar serves as a heat shielding spacer for axially spacing the LED apart from the light-sensitive sensor so as to minimize the mutual thermal influence. In accordance with U.S. Pat. No. 7,413,543 B2 the cooling chamber collar and the conductor plate including the LED mounted thereon form a separate independent functional unit that is pre-assembled outside the endoscope cap and is then inserted in the cap.
As a result, supports for the cooling chamber collar have to be formed in the endoscope cap. These supports further limit the space available which is quite limited anyway and render the manufacture of the endoscope cap more expensive.
In view of these problems it is the object of the present invention to further develop the endoscope head of a preferably medical endoscope so that it achieves higher efficiency. It is one target to minimize the costs for the manufacture thereof. It is ultimately a target of the invention to obtain more free space by appropriate arrangement and allocation of the individual functional units which free space can be used for additional functional units or enlarged individual functional units.